When a Windows Vista-based computer is in hybrid sleep mode, the Wake On LAN (WOL) functionality may not wake the computer from hybrid sleep. This problem may occur in both wired and wireless network environments.

Consider the following scenario:

• A Windows Vista-based computer is awakened from sleep by a magic packet.
• The WakeOnLAN feature is enabled on the computer.

In this scenario, the computer desktop is displayed unexpectedly.

Note: For more information about magic packets, see the “More information” section.

On a Windows Vista-based computer, you turn on the “wake from sleep” option for a network adapter that supports Wake On LAN (WOL) functionality. After you do this, the computer does not wake from sleep when it receives network traffic.

For example, you click to select the Allow this device to wake the computer check box on the Power Management tab of the properties dialog box for the network adapter. You install the sample PassThru driver that is included in the Microsoft Windows Driver Kit (WDK), or you install a virus scanner that uses the same PassThru driver technology. Then, you put the computer to sleep. However, the computer does not wake from sleep when you send a PING command or a “magic” packet.